Climate regime shift and forest loss amplify fire in Amazonian forests

Area of Science:

• Environmental Science
• Climate Science
• Ecology

Background:

• Amazonian fires have increased in frequency over the past decade.
• This trend is linked to altered hydrological cycles, with conflicting evidence of increased precipitation versus drought.
• Previous studies noted changes in precipitation and drought severity impacting fire regimes.

Purpose of the Study:

• To demonstrate compelling evidence of increased fire susceptibility in Amazonia.
• To investigate the role of climate regime shifts and forest loss on fire frequency.
• To understand the feedback mechanisms between forest loss, climate change, and fire.

Main Methods:

• Utilized multiple satellite observations.
• Employed climate reanalysis datasets.
• Analyzed changes in atmospheric conditions and hydrological cycles.

Main Results:

• Accumulated forest loss since 2000 has warmed and dried the lower atmosphere, reducing moisture recycling.
• This resulted in increased drought extent and severity, leading to subsequent fires.
• Extremely dry/wet events and hot days have become more frequent, while increased rainfall did not mitigate severe droughts.

Conclusions:

• Amazon fire risk is highest in the southeastern region and expanding northward.
• Tropical forests are less resilient to climate shifts and forest loss, increasing their susceptibility to fire.
• Findings imply the need for forest conservation and fire protection to mitigate positive feedback loops.